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1.
NO与OH自由基反应机理的理论研究   总被引:1,自引:5,他引:1  
用MP2方法,在6-311 G(d,p)基组水平上研究了NO与OH自由基反应的微观机理,全参数优化了反应过程中各反应物、中间体、过渡态和产物的几何构型,考虑零点能校正,同时采用QCISD(T)/6-311 G(d,p)方法得到了更为精确的能量.振动分析结果证实了中间体和过渡态的真实性,IRC计算结果进一步证实了过渡态的真实性.从对NO与OH自由基反应机理的研究结果看,NO与OH自由基反应为双通道反应过程,分别为:NO OH→IM1→TS1→NO2 H,NO OH→IM1→TS2→IM2(HNO2).研究发现,通道NO OH→IM1→TS2→IM2(HNO2)是NO与OH自由基反应的主反应通道,其主要产物是HNO2.  相似文献   

2.
本文使用Gaussian98程序包,在B3LYP/6—311++G**基组水平上,用振动模式分析和电子布居分析对CH2CIO与NO自由基反应体系的反应机理进行了量子化学研究.研究结果表明,CH2CIO+NO→IM1→TS1→IM2→TS3→OCHCl+HNO为主反应通道,OCHCI+HNO为主产物.  相似文献   

3.
本文使用Gaussian98程序包,在B3LYP/6—311++G**基组水平上,用振动模式分析和电子布居分析对CH2CIO与NO自由基反应体系的反应机理进行了量子化学研究.研究结果表明,CH2CIO+NO→IM1→TS1→IM2→TS3→OCHCl+HNO为主反应通道,OCHCI+HNO为主产物.  相似文献   

4.
本文以恒界面池法研究了HNO3介质中TiAP对Th(Ⅳ)的萃取动力学性质.在一定条件下,考察了萃取时间对萃取率的影响,并测定了搅拌速度、温度、界面积以及各反应物初始浓度对萃取速率的影响.实验结果表明:萃取体系在约6h后达到平衡;搅拌速度(120-180rpm)对萃取速率无显著影响,萃取反应的活化能为23.20kJ/mol,萃取过程为界面反应的混合控制模型.在HNO3介质中,TiAP萃取Th(Ⅳ)的化学反应速率方程为:r=-dcTh(NO3)4/dt=k[Th(NO3)4]1.05[TiAP]1.77[HNO3]0.38,其中,k=1.6×10-2(mol/L)-2.2·s-1.  相似文献   

5.
利用STANJAN对甲烷(CH4)、丙烷(C3H8)及辛烷(C8H18)3种燃料与空气(21%O2与79%N2的混合物)在不同混合比下燃烧后产生的CO,NO,NO2的浓度及火焰温度进行了计算。结果表明3种燃料燃烧后的绝热火焰温度及3种产物浓度的变化趋势类似;且随着燃料碳氢比的上升,绝热火焰温度和3种产物的浓度随之上升。  相似文献   

6.
以Bi( NO3)3·5H2O为原料,利用弱碱并流沉淀法制备Bi2O3粉体,实验结果表明最佳的工艺条件为:反应温度为30℃,Bi(NO3)3溶液的浓度为0.20 mol/L,最佳反应pH为8.XRD分析结果表明产物为α - Bi2O3,晶粒尺寸约为34 nm.  相似文献   

7.
基于NOx气体的资源化处理考虑,研究了水和不同浓度的稀硝酸对NO2的吸收性能,考察了吸收剂用量、稀硝酸的浓度(3%~30%)以及气相压力对NO2吸收效果的影响。结果表明,增加吸收剂用量、硝酸浓度和气相压力均能提高NO2的吸收效率,其中稀硝酸用量对吸收效率的影响特别显著。水吸收NO2是化学吸收与物理吸收并存的复杂过程,气液两相中存在溶质(NO2、N2O4等)和生成物(HNO2、HNO3等)的物理扩散和化学反应。该文分析了各种吸收条件下吸收液中亚硝酸和硝酸的浓度组成关系,讨论了吸收前后气相中NO2、N2O4的组成变化,证明了NO2在水中的吸收是以N2O4与水的化学反应为主。  相似文献   

8.
利用量子化学理论方法。研究了与大气臭氧层损耗密切相关的自由基反应NH2+ClO的微观机理。在密度泛函B3LYP/6-311+G(d,p)水平上优化得到反应路径上的反应物,过渡态,中间体和产物的几何构型,并通过振动频率分析对过渡态和中间体进行了确认。在高级电子相关组态相互作用QCISD(T)/6-311+G(d,p)水平上进行了单点能计算,得到了反应体系的势能面信息,结果表明,该反应经过缔合、H-转移和离解等过程,最终可以得到五种产物,分别为H2NO+Cl,H2NClO,HCl+HNO,H2+NO+Cl和NH+HClO,由于形成产物H2NO+Cl的活化势垒较低,因而是主要反应通道,而形成产物NH+HClO的通道从动力学上看是最不利的。  相似文献   

9.
以包头混合型稀土精矿为研究对象,在密闭条件下,采用Al(NO3)3-HNO3盐溶液浸出包头混合型稀土精矿中的稀土。考察Al(NO3)3浓度、HNO3浓度、浸出时间、液固比、浸出温度和搅拌速度等因素对包头混合型稀土精矿中稀土浸出率的影响规律以及稀土浸出过程中的动力学分析。研究结果表明:当HNO3浓度为3 mol/L,Al(NO3)3浓度为1.5 mol/L,浸出温度为100℃,搅拌时间为90 min,液固比为30 mL/g,搅拌速度为300 r/min为最优浸出工艺条件。在此优化条件下,精矿中稀土的浸出率为73.5%,而稀土的理论浸出率为74.82%,即精矿中稀土浸出率达98.24%;浸出过程属于收缩反应核模型,反应活化能为34.213 kJ/mol,受边界传质和扩散混合控制。  相似文献   

10.
用热重分析仪(TGA)研究了250~500℃烟气中NO对干法脱硫法反应的影响规律。实验采用分析纯C aO作为脱硫剂与模拟烟气反应。TGA实验结果表明,在250~500℃的范围内,NO对干法脱硫反应有促进作用。并且存在最佳的NO促进脱硫反应进行的温度和浓度范围:最佳温度为300℃,最佳浓度为2.009~3.348 g.m-3。对脱硫产物的Fourier变换红外分析(FT IR)和扫描电镜(SEM)分析表明NO是通过增加反应活性位和改变反应途径促进干法脱硫反应的进行。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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